1. Field of the Invention
The present invention relates to a microwave calorimeter and particularly to a microwave calorimeter which measures total microwave energy with a high energy sensitivity at both high and low power levels.
2. Description of the Prior Art
Many different apparatuses have been proposed for measuring the total microwave energy of an applied microwave signal or pulse.
One type of apparatus for measuring total microwave energy is a temperature sensing calorimeter which determines the energy of an applied microwave pulse by measuring the rise in temperature of a load which absorbs the applied microwave energy. This energy absorbing load can be, for example, a microwave absorbing fluid (such as water or octonal) or a microwave-absorbing ceramic (in, for example, the form of a hollow cylinder). However, such temperature sensing calorimeters are insensitive at lower microwave energies and get more insensitive at longer wavelengths.
Another type of apparatus for measuring total microwave energy is a pyroelectric detector which converts the microwave energy impinging thereon into an electrical signal proportional to the applied energy level. However, Basically such pyroelectric detectors are only good for low power levels at short wavelengths.